CVE-2026-8718
- Source
- https://cve.org/CVERecord?id=CVE-2026-8718
- Import Source
- https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-8718.json
- JSON Data
- https://api.test.osv.dev/v1/vulns/CVE-2026-8718
- Aliases
-
- GHSA-p3r6-mx6c-33gq
- Published
- 2026-08-10T22:40:26.836Z
- Modified
- 2026-08-12T04:25:03.736543521Z
- Severity
-
- 8.4 (High) CVSS_V3 - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:H CVSS Calculator
- Summary
- Out-of-bounds write in DTLS peer Connection ID getsockopt (`TLS_DTLS_PEER_CID_VALUE`) in Zephyr net sockets/TLS
- Details
-
tlsoptdtlspeerconnectionidvalueget() in subsys/net/lib/sockets/socketstls.c, which handles getsockopt(SOLTLS, TLSDTLSPEERCIDVALUE), passed the caller-supplied optval directly to mbedtlssslgetpeercid() without verifying the buffer was at least MBEDTLSSSLCIDOUTLENMAX (default 32) bytes. mbedtlssslgetpeercid() copies the peer-negotiated DTLS Connection ID (length 1..MBEDTLSSSLCIDOUTLEN_MAX) into that buffer without a destination-size parameter, so a caller-supplied optlen smaller than the CID causes a write of up to 31 bytes past the buffer end.
In CONFIGUSERSPACE builds the getsockopt syscall verifier (zvrfyzsockgetsockopt) bounce-buffers the user's optval into a kernel allocation of exactly optlen bytes (kusermodeallocfromcopy -> zthreadmalloc), so an unprivileged user thread that passes a small optlen on a connected DTLS socket with Connection ID enabled induces a kernel-heap buffer overflow, with the overflowing content being the remote peer's CID.
The defect requires CONFIGMBEDTLSSSLDTLSCONNECTIONID, an established DTLS session with a negotiated peer CID, and (for the kernel-crossing case) CONFIGUSERSPACE. Introduced when the TLSDTLSCID option was added (v3.5.0).
The fix rejects callers whose optlen is below MBEDTLSSSLCIDOUTLEN_MAX with -EINVAL.
- Database specific
{ "cna_assigner": "zephyr", "cwe_ids": [ "CWE-787" ], "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/8xxx/CVE-2026-8718.json" }- References
-
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/8xxx/CVE-2026-8718.json
- https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-p3r6-mx6c-33gq
- https://nvd.nist.gov/vuln/detail/CVE-2026-8718
- https://github.com/zephyrproject-rtos/zephyr/commit/aa317825a55a401315e8e17f620c70c02e8f176d
- https://github.com/zephyrproject-rtos/zephyr